Methods of Manufacturing a Semiconductor Device

Abstract

Methods of manufacturing a semiconductor device and an apparatus for the manufacturing of semiconductor devices are provided. An embodiment regards providing a process which changes the volume of at least one layer of a semiconductor substrate or of at least one layer deposited on the semiconductor substrate, and measuring a change in volume of such at least one layer using fluorescence. In another embodiment, a change in volume of such at least one layer is measured using reflection of electromagnetic waves.

1 . A method of manufacturing a semiconductor device, the method comprising:
 providing a semiconductor substrate; and   producing at least one structured layer in the semiconductor substrate, such producing comprising:
 providing a process that changes volume of a portion of the semiconductor substrate, the portion of the semiconductor substrate comprising a region of a wafer, at least one layer of the semiconductor substrate or at least one layer deposited on the semiconductor substrate; and 
 measuring a change in volume of the portion of the semiconductor substrate using fluorescence. 
   
   
   
       2 . The method according to  claim 1 , wherein measuring the change in volume comprises providing at least one incidence X-Ray beam and measuring an intensity of fluorescence radiation such that the use of fluorescence includes the use of X-Ray fluorescence. 
   
   
       3 . The method according to  claim 2 , wherein a penetration depth of the incidence X-Rays into the at least one layer is tuned by varying an angle of incidence of the incidence X-Ray beam. 
   
   
       4 . The method according to  claim 2 , wherein the incidence X-Ray beam is provided at grazing incidence. 
   
   
       5 . The method according to  claim 1 , wherein a change in volume is detected locally by measuring fluorescence of local areas of the portion of the semiconductor substrate penetrated by an incidence electromagnetic beam. 
   
   
       6 . The method according to  claim 1 , wherein fluorescence is measured at least at a first time and a second time during the process that changes the volume of the at least one layer, and a change in volume is determined by the difference in fluorescence between the first and second times. 
   
   
       7 . The method according to  claim 1 , wherein there is provided a top first layer the volume of which is changed during the process, and an underlying second layer the volume of which is not changed during the process, wherein the first layer comprises a first material having a fluorescence radiation with a first wavelength, and the second layer comprises a second material having a fluorescence radiation with a second wavelength, and wherein both layers are subjected to electromagnetic radiation. 
   
   
       8 . The method according to  claim 7 , wherein the fluorescence signal of at least one of the first and second layers is evaluated to determine the end point of the change-in-volume process. 
   
   
       9 . The method according to  claim 7 , wherein
 the change-in-volume process comprises an etching process;   the fluorescence signal of the second layer is measured; and   an end point is detected when the fluorescence signal of the second layer reaches a specified strength.   
   
   
       10 . The method according to  claim 9 , wherein the reaching of a specified strength of the fluorescence signal of the second layer corresponds to a specific open area of the second layer produced by etching the first layer. 
   
   
       11 . The method according to  claim 9 , wherein the etching process comprises a spacer etch in the course of a sublithographic patterning process and the reaching of a specified strength of the fluorescence signal of the second layer identifies an end point of the spacer etch in which a specific area of the second layer has been opened between the etched spacers. 
   
   
       12 . The method according to  claim 7 , wherein
 the change in volume process is a deposition process;   the fluorescence signal of the second layer is measured; and   an end point is detected when the fluorescence signal of the second layer reaches a specified minimum.   
   
   
       13 . The method according to  claim 12 , wherein the reaching of a specified minimum of the fluorescence signal of the second layer corresponds to a specific thickness of the first deposited layer. 
   
   
       14 . The method according to  claim 1 , wherein the process which changes the volume of at least a layer of the semiconductor substrate or a layer added to the semiconductor substrate is an etching process or a deposition process. 
   
   
       15 . A method of manufacturing a semiconductor device, the method comprising:
 providing a semiconductor substrate; and   producing at least one structured layer in the semiconductor substrate, such producing comprising:
 providing a process that changes the volume of at least one layer of the semiconductor substrate or at least one layer deposited on the semiconductor substrate; and 
 measuring a change in volume of such at least one layer using reflection of electromagnetic waves. 
   
   
   
       16 . The method according to  claim 15 , wherein
 the substrate is irradiated with X-Rays;   X-Rays reflected by the substrate are measured, and a signal is provided indicative of the intensity of the reflected X-rays; and   the signal is evaluated to determine the change in volume of the at least one layer.   
   
   
       17 . The method according to  claim 16 , wherein a decrease of the signal is associated with a reduction in thickness of the at least one layer and an increase of the signal is associated with a increase in thickness of the at least one layer. 
   
   
       18 . The method according to  claim 15 , further comprising providing a top first layer of the semiconductor substrate and an second layer of the semiconductor substrate beneath the first layer, the two layers having a different refractive index. 
   
   
       19 . A method of manufacturing a semiconductor device, the method comprising:
 providing a semiconductor substrate;   providing a top first layer of the semiconductor substrate and a second layer of the semiconductor substrate beneath the first layer, the two layers having a different refractive index for X-Ray radiation; and   etching the first layer of the semiconductor substrate, and during etching:
 irradiating the substrate with X-Rays; 
 measuring the X-Rays reflected by the substrate, and providing a signal indicative of the reflected X-rays; 
 determining a change in the signal; and 
 associating an end point of the etching process with the change in the signal. 
   
   
   
       20 . The method according to  claim 19 , wherein the signal experiences a drop-off that corresponds to a drop in the reflected X-Ray intensity, and wherein this drop-off is associated with an end point of the etching process. 
   
   
       21 . The method according to  claim 19 , wherein
 the material of the first layer is chosen such that it has a first critical grazing angle of total reflection for X-Ray radiation;   the material of the second layer is chosen such that it has a second critical grazing angle of total reflection for X-Ray radiation, the second critical angle being smaller than the first critical angle; and   X-Rays are irradiated at the substrate at a grazing angle of incidence that is smaller than the first critical angle of total reflection for the material of the first layer and larger than the second critical angle of total reflection for the material of the second layer.   
   
   
       22 . The method according to  claim 21 , wherein,
 before material of the first layer is etched away, total reflection of the incident X-Rays occurs at this material; and   when material of the first layer is etched away, the X-Rays are incident on the material of the second layer where they do not experience total reflection such that there occurs a drop in reflected intensity.   
   
   
       23 . The method according to  claim 19 , wherein etching includes etching of lines and spaces or a line etch and the X-Rays are irradiated in a direction parallel to the lines and spaces or lines. 
   
   
       24 . A method of manufacturing a semiconductor device, the method comprising:
 providing a semiconductor substrate;   providing a process which etches a top first layer of the semiconductor substrate or produces such layer, wherein a second layer of the semiconductor substrate is located beneath the first layer, wherein   the materials of the first and second layers and the angle of incidence of the incident X-Rays are chosen such that total reflection of the incident X-Rays occurs or disappears when material of the first layer or at least parts of the first layer has been processed,   the occurrence or disappearance of total reflection corresponding to an increase or drop in the intensity of the reflected X-Rays.   
   
   
       25 . An apparatus for the manufacturing of semiconductor devices, the apparatus comprising:
 means for changing the volume of at least one layer of a semiconductor wafer or at least one layer deposited on the semiconductor wafer;   an X-Ray radiation source;   an X-Ray detection device detecting and measuring a signal indicative of the intensity of X-Rays reflected or emitted by fluorescence by the semiconductor wafer when irradiated with X-Rays by the X-Ray radiation source; and   evaluating means for associating the signal with the change in volume process.